Automatic electric excavating-bucket.



W. G. STEPHAN 6v C. E. BEARD.

AUTOMATIC ELECTRIC EXCAVATING BUCKET. APPLIUATION FILED JULY 1a, 1910.

1,043,640. l Patented Nov. `5, 1912.

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W. G. STEPHAN & c. E. BEARD.

AUEIOMAIIC ELECTRIC BXGAVATING BUCKET. APPLIUATION FILED JULY 1s, 1910.

1,043,640. Patented Nov.5,1912.}

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UNITED STATES PATENT oEEroE. i

Wei-TER G. sTErHnN, or CLEVELAND, AND CLEMENT n. BEAM. or COLUMBIANA,

OHIO.

Specification of Letters Patent.

Patented Nov. 5, i912.

Application filed July 18, 1910. Serial No. 572,540.

To all whom 'it may concern:

Be it known that we, VALT in G. STEPHAN and CLEMENT E. BEAR, citizens ot the United States, and residing, respectively, at Cleveland', Ohio, and Columbiana, Ohio, have invented certain new and useful Improvenients in Automatic Electric Excavat* of which the follovv'ing is a Our invention relates to means for operating excavatingbuckets o1 the clamshell-- type, and cne'ot its objects is to simplify l the opt-:ration of excavating buckets and increase their elticiency by reducing the number of cables necessary to operate Vthe bucket electrically, by obtaining perfect control from a distant. point of all the movements ot the bucket, no matter what its position, by increasing the speed ot' operation by eliminating hand brakes, clutches, etc., tor operating the bucket, by lessening head room re quired for operation of the bucket and by securing other advantages. 1

A further object of the invention is the provision of automatic mechanism carried by the bucket for controlling one or more electric motors also carried by the bucket.

Other objects of the invention will appear more fully hereinafter, the novel combinations of elements being setforth in the appended claims.

ln the accompanying dra\vings-'Figure 1 shows a side view of' a clam shell bucket and .two electric motors within the same in dotted lines; Fig. 2 is a side view of Fig. 1, .showing the bucket closed in full lines and open in dotted lines, and by additional dotted lines showing the interior motors and the automatic limit switch mechanism, overload device and reversing switch; Fig. 3 is a diagramn'iatic illustration of a system of circuits which may be employed in combination with our invention.

In Figs. 1 and 2 we have 4shown an excavating bucket ot the clamshell. type cornprising shells l() and 101 suspended from the inclosing casing 9 by means of the rock shafts 11, 111 and levers 12, 121. Integral with the. downwardly extending levers 12, 121 are upwari'lly extending levers 13, 131, respectively; to the upper ends of the latter are pivoted at 4S, 481 the links 14, 1111, the lower ends of which cross each other and are pivoted to upper inner corners ,of the shells 10, 1()1 at 15, 151, respectively, as

shown in ,Fig 2. As indicated in Fig. 1 the shafts 11, 111 extend entirely through the lower portion of the casing 9 and the .levers 12, 13 and 121, 131y are keyed thereto to rotate therewith and are located on the outslde of the casing 9 there being a'duplicate set of levers 12, 13, and 121, 131 on the The lower ends of these gears are connected as indicated at 18 in Fig. 1 to the shafts 16, 161, respectively midway between the ends thereof. The upper side of the gears 17 171 are in mesh with the worms 19, 191, respectively, which are carried at the ends of a shaft 23 mounted in suitable bearings 2.1-, 22 and 211, 221 supported on the cross-pieces 20, 201 extending from one wall of the, casing 9 to the other horizontally and rigidly fastened to said, walls. Intermediate the ends of the worm shaft. 23 is connected a spur gear Wheel 24 in mesh with which is a 'pinion 25 on the shaft of the motor 26, preferably an electric motor. 'We prefer to mount two electric motors 26, 261 within the casing 9 by fastening the same rigidly to the walls thereof, as indicated in Fig. 1, and provide each of these motors with a pinion 25, 251, respectively in mesh with the same gear wheel 241. When the electric motors are operated each drives its pinion in the same direction and each transmits motion to the gear wheel 24 which in turn rotates the Worm Shaft 23 to rotate the worms 19,191 and thus cause the segmental .worm gears 17, 171 to turn and open the shells to the dotted line positions 49, 491 or close the same to the full line positions.

i Whether electric motors are used or not we prefer to transmit the power to themetors through the interior of 44the haulage cables. ln this instance we have shown two suspending cables 27, 271 spaced apart and connected to the upper sideof the casing 9. We employ two ca les to prevent the bucket 55 l the bucket shells arein closed position the source of electric current sup ly through the .fusesB to the main line kni e switch C. D designates an automatic no-Voltage starting rheostat to which overload release' mechanisln may be added but we have in this in-v stance shown a separate overload circuit breaker N. Eis a pilot lamp'ot comparatively high resistance lconnected Vacross the lmains between the rheostat D and the hoisting mechanism.` F designates-contact or slip rings on the hoisting drum on which the cables 27, 271 are wound or vunwound, the respective ends of said cables having'their interior conductors connected to said slip rings. M designates the insulated wires in the' haulage cables. G are the binding posts lWithin the'bueket shell. H designates the solenoid brake mechanism for the series Wound electric motors, the armatures 'of vwhich are indicated at I, I1, and the Held windings by the reference characters L,L1. J is the pole changing or motor reversing switch controlled by the bucket mechanism as heretofore explained or by the solenoid magnet K upon overload as hereinafter described. l

The operation of our automatic electric excavating bucket is asfollows: lAssuming ythat the shells are in closed position, as shown in Jfull lines in Fig. 2, and it is desired to open the same, the main line switch C (Fig. 3) is elosed'and the-lever of the rheostat D gradually moved against the action of thespring 33 over the contaetsconnected to the sectional starting resistance 35 until thelever rests against and is held by 'the magnet 34, the lever being constructed 'of' iron or having an armature attached to the same. W'hen the switch Cis closed and the lever. of the rheostat D moved onto the tirst live Contact a circuit is established from one of the mains through the starting resistance 35, upperslip'ring F, right-hand conductor M to the reversing switch J. `When reversing switch J is on the contacts and 7,

, conductor 41, .brake solenoids r42, 421,

4a'nd 'therefore the circuit will continue l through the blade 36,'"contact 7, conductor 37, armatures I, I1, conductor 38,'contaet 6, blade 39, eonductor'40, ieldwindings L1,'J'IJ,

le t- `,handconductor Mplower slip ring F, conduetor 43, solenoid` 44 of the overload eircuit breaker, contacts 45, conductor 46, and

thence through the lower blade of switch C to the negative main. As soon as this circuit is established, the brakes of the motors 26, 261, within the easing 9 will be released and the motors will begin to rotate slowly and as the rheostat D is operated their speed will accelerate to full speed. As the motors rotate, motion i's transmitted through the pinions 2157, 251 to the gear wheel 24 which in turn imparts motion :to the worm shaft 23. The worms 19, 191 will then positively actuate. the segmental Worm gears 17, 171 to rock the shafts 11, 111 and lift the shells 10, 101 by their ears 47, 471, respectively. At the same time the shells are pushed apart by the upper arms 13, 131 acting on the links 14, 141 which are pivoted at their upper ends at 48, 481 to the arms 13, 131, and at their lower ends to the shells 10, 101 at 151, 15, respectively.

In the opening operation of the bucket shells, when the latter approach their extreme open positions, as indicated by the dotted lines 49', 491, the right-hand lever 131 engages a pin 50 which extends outwardly through the casing 9 and is connected at its inner end to a lever 51, which is pivoted at 52 and has a pin and slotconnection at 53 to a link 54 which is connected to the cross piece of the reversing switch J. When the lever 131 thus engages the pin 50 the lever 51 is tilted on its pivot 52 and the reversing switch J operated to the position shown in Fig. In this operation the blades 39 and 36 are moved entirely off the contacts 6 and 7 before they engage the contacts 7 and 8, respectively. As soon as the blades 39 and 36 leave the contacts 6 and 7 the circuit is interrupted and the magnet 34 becomes denergized allowing the'spring 33 to cause the lever of the rheostat D to fly `back to zero, open or neutral position and rmagnets the brakes will be released only when the motors also receive current t'or starting.' `We do no-t wish to be limited to this particular arrangement, however, although we deem it preferable, as in some instances a shunt wound electric motor could be used and thel brake magnet connected in shunt to the conductors M.

Itshould be noted that the emergenrv solenoid K has notv been in circuit duringl the op'enil'lg of the shells but when the rei versing switch .I has been moved into vits position shown in Fig. 3, the solenoid l( is connected 1n' circuit between the motor ar obstruction.

matures Il and the contact 8 by the conduc tors 59 and 60. The spring 55 between the magnet K and the pivot 56 acts on the lever 57 tending to press it down and through he pin and slot connection 53' reverse the position of the reversing switch J. The arm 131 .resting against the pin 50 and being held there, holds the reversing switch J in the position indicated in Fig. 3.

rl ow, while the bucket is fully open, if -it is desired to close the shells, the operator at the starting box D moves the lever to on position thus establishing a circuit, but as to the armatures I, I1 in a reverse direction. This circuit is from the positive main through the starting resistance D, conductor M, blade 3G, conductor 59, solenoid K, conductor G0, armatures I1, I, conductor 37, blade 39, cohductor 40, field windings L1, L, conductor 41, brake solenoids 42, 421, conductor M, conductor/43, and thence through the overload circuit breaker to the negative main. The magnetV K being immediately energized will hold the reversing switch J in its upper position against` the action ot the spring 55. Thebrakes of the motors' being released the latter will rotate and asy the starting resistance 35 is cut, will .increase in speed. The motors now rotate in the opposite direction to close the shells and will continue to rotate until a dog G1 on the left bucket arm lifts the lug 62.011 the switch arm 57 which is pivoted to the casing 9 at 58. This takes place when the bucket is Jmully closed and moves the armature ori plunger ot the magnet K down and also the reversing switch J. The latter, when in its intermediate position, linterrupts the circuit and causes the magnet 34 to become denell;r gized and therefore release the arm of the rheostat D to initial or open position, as in-l dicated in Fig. 3. lVhen fully Iclosed and carrying a load the bucket is etectually locked in closed position by the wornlgeari ing connections between the motors and`the shells.

H there should be an overload in the bucket or if the shells 'should in closing bite a solid substance, the increased current'due to the decrease in the counter electro-motive force in the motors within the bucket, will cause the circuit breakerl N to separate the contacts 45 and thus interrupt the circuit and prevent damage to the motors. The lever ol the rheostat l) flies back to initial position, the brakes of the motors are applied and the motors stopped. The magnet K being denergized by this operation the reversing switch J will be reversed so that upon restablishment of the circuit to the motors, the shells will move away from the Theoperation of closing the shells to grab another loadmay then be repeated without causing an overload.

the shells oft said bucket, a reversing switch tor said motor and also carried by said bucket, and automatic means on the bucket for operating said reversing switch.

2. The combination with bucket, of an electric motor carried thereby,

connections between said motor and the jaws* ol said bucket to open and 'close the same, a reversing switch carried by the bucket, and mechanism enacting with the relatively movable parts of said bucketto` automatically operate said reversing switch.

3. The combination. with a clam-shell bucket, of a casing connected'v thereto, an electric motor within the casing, worm gearing for transmitting motion :trom said motor to the shells of said bucket, a re# ver-sing switch ior the motor and carried by said bucket, and automatic means for.

'operating said reversing switch..

4. The combination with a clam-shell bucket, of an electric motor carried thereby, operating connections between said motor 'andthe jaws of said bucket, means for auto matica-lly stopping the motor upon overload, a reversing switch for said electric motor and carried by said bucket, and automatie mechanism for setting said reversing -switch in such position that upon re-supplying said motor with current the bucket will be moved to fully open position.

5. rlhe' combination with a clam-shell bucket, of an electric motor carried thereby, worin gearing connections between said m0- tor and the shells of said bucket, a motor reversing switch carried by the bucket, and means also carried by the -bucket for automatically operating said reversing switch.

6. The combination with a clam-shell bucket, ot' an electric motor for operating the same, a reversing switch for said motor, means actuated by the movement of the jaws of said bucket for operating said reversing switch, and a vertically arranged electromagnet for holding said reversing switch in oneot its positions after said means becomes ineffective, said reversing switch automatically assuming its other position when said electro-magnet becomes denergized.

i'. The combination with a clameshell Obviously, those skilled .in the vart mayW -bucket, ofV an electric motor carried thereby,

a clam-shell i a reversing switchior said electric motor, driving connections between said motor and the shells of said bucket, mechanism coacting with said connections for operating said reversing switch when the bucket is fully closed or fully open, and an electromagnet for holding the reversing switch in one of its positions when said reversing switchy operating mechanism is released by the movement of said shells from fully open or fully closed position.

8. The combination with a clam 'shell excavating bucket, of an electric motor carried thereby, operating connections between said motor and the .shells of said bucket, a

Areversing switch for said motor, means for operating said reversing switch and effecting'the stopping of said motor when the bucket is entirely open or entirely closed, a magnet operatively connected vto said reversing switch, and a spring for moving 'said reversing switch to initial position'upon denergization of said magnet.

9. The combination with a clam shell bucket, of an electric motor carried thereby, operating connections between said motor Aand the shells of said bucket, a reversing switch for the motor and carried by said bucket, mechanism co-acting with the shells of said bucket for automatically stopping t-he moto-r when the bucket is entirely. open,

cal brake for said motor, means Afor effectingr the application of the brake to stop the motor when the bucket is entirely opened or entirely closed, a reversing switch carried by the bucket, and automatic mechanism for placing said reversing switch in such position as to eiiect a reversal of the motor upon restablishment of the current.

11. The combination' with a clam shelldriving connections between said motor and the shells of said bucket, a reversing switch carried by said bucket, levers pivoted to said bucket and connected to said reversing switch, one of said levers being actuated when the bucket is entirely o en and the other being actuated when the ucket is'entirely closed, and an electro-magnet for holding said reversing switch in the. position l in which it was put by the completeepenng" of the bucket. v,

12. The combination with a clam shell bucket, of an electric motor carried thereby, driving connections between said motor and the shells of said bucket, a reversing switch for the motor, mechanism co-acting with said connections for positively moving said reversing switch to one of its positions when the bucket is entirely open, an electro-magnet for holdingsaid reversing switch in such position when said moving mechanism is released by the return of said shells toward closed position, means for automatically eiecting the denergization of the said electro-magnet when the shells are obstructed' inthe closing operation, and a spring for vmoving the reversin switch to its other position when the 'sai energized.

. In testimony whereof we have signed our names to this specification, in the presence of two subscribing witnesses, on this {ifteenth day of July A. D. 1910.

WALTER G. STEPHAN. e CLEMENT E. BEARD.

Witnesses:

GEO. A. WELCH, D. O. MCHUGH.

electro-magnet is de- 5b' bucket, of an electric motor carried thereby, 

